to say "ee" while you are auscultating. Normally, a muffled

long E sound is heard. When "ee" is heard as "ay;' egophony

is present and indicates an underlying consolidation. Tactile

fremitus refers to an increase in the palpable vibration transmitted through the bronchopulmonary system to the chest

wall when a patient speaks. Increased tactile fremitus suggests

an underlying consolidation.

DIAGNOSTIC STUDIES

..... Laboratory

In ambulatory, mildly symptomatic patients who are other ­

wise healthy, no testing may be indicated. The diagnosis of

pneumonia is often clinical, but laboratory studies may aid

in the diagnosis or treatment decisions. There is often an

elevated white blood cell count in patients with bacterial

pneumonia. Obtain a chemistry panel in ill-appearing

patients to rule out metabolic derangements. For patients

who are hospitalized with pneumonia, obtain blood cultures

before initiating antibiotics (if possible). Do not delay anti ­

biotics for critically ill patients. More than 25o/o of hospital ­

ized patients with pneumonia have bacteremia. Sputum

Gram stain and cultures are rarely obtained in the emer ­

gency department (ED), but can help determine the bacte ­

rial pathogen and narrow specific antimicrobial therapy.

..... Imaging

Chest x-ray (CXR) may demonstrate evidence of pneumonia, but cannot be relied on to completely exclude pneumonia (especially in immunocompromised patients). Typical

findings on CXR include lobar consolidation, segmental or

subsegmental infiltrates, or an interstitial pattern (Figure 23-1).

Cavitation is seen with anaerobic, aerobic gram-negative

bacilli, S. aureus, and mycobacterial or fungal infections

(Figure 23-2). Radiologic findings are nonspecific for

PNEUMONIA

.A Figure 23-1 . Chest radiograph showing pneumonia

in the right middle lobe.

.A Figure 23-2. Chest radiograph of a patient with

tubercu losis. Note the bi lateral apical infiltrates and

the cavitary lesion in the left upper lobe .

predicting a particular infectious etiology and can lag behind

clinical findings. Also, radiographic signs of pneumonia can

persist well after clinical resolution.

MEDICAL DECISION MAKING

The differential diagnosis of patients with a cough and

CXR abnormality includes pulmonary embolism, congestive heart failure, lung cancer, connective tissue disorders,

CHAPTER 23

Cli nical suspicion of

pneumonia

pneumonia

Consider discharge

to home

Search for alternative

diag nosis or treat for

pneumonia presumptively,

based on clinical findings

Figure 23-3. Pneumonia diag nostic algorithm. CXR, chest x-ray.

granulomatous disease, fungal infections, and chemical or

hypersensitivity pneumonitis. The radiographic signs of

pneumonia vary, so it is difficult to predict the causative

organisms by the radiographic appearance alone. The

clinical presentation, in conjunction with CXR findings,

will aid in treatment decisions (Figure 23-3 ).

TREATMENT

Start with supplemental oxygen by nasal cannula or face

mask if the patient is short of breath or hypoxic. For

patients with severe respiratory distress or shock, mechanical ventilation can decrease the work of breathing and can

be lifesaving.

Empiric antibiotics can be started based on the likely

pathogens and overall clinical picture. Timely administration of antibiotics ( <6 hours from presentation) is associated with improved outcomes for patients requiring

hospital admission. The antibiotic recommendations listed

are representative of recommended treatments, but are not

comprehensive (Table 23-1). Other antibiotic regimens

may also be effective, and the clinician should consider

local resistance patterns and allergies.

Consider whether or not your patient requires measures

to prevent transmission of disease. These include droplet

and airborne precautions. When the pathogen has not been

identified, err on the side of caution and apply the precaution based on the suspected pathogen. These measures

PNEUMONIA

Table 23-1. Recommended antibiotic reg imens to treat pneumonia.

Outpatients age <60 years and otherwise Consider azithromycin (500 mg PO for 1 day, then 250 mg PO for 4 days) or levofloxacin (750 mg

healthy PO daily for 14 days) or doxycycline (100 mg PO bid for 14 days)

Outpatients age >60 years or with

comorbidities (without HCAP}

Consider amoxicillin·clavulanate (2 g PO bid for 14 days) plus azithromycin or levofloxacin (750 mg

PO daily for 14 days)

Admitted with CAP Third-generation cephalosporin (ceftriaxone 1 g IV dai ly) and a macrolide (azithromycin 500 mg IV

dai ly}